A conventional flow meter is structured with a housing wherein is formed a flow path that is attached to piping above and below, through which a fluid that is to be measured flows, to form a flow path that is connected to an enclosing portion in the center of a main unit, and a flow meter unit that is attached removably to this housing. The flow meter unit is structured from a measuring portion, enclosed within the enclosed portion, that has a rotor that rotates in accordance with the flow rate of the fluid, and a detecting portion for detecting the speed of rotation of the rotor. See, for example, Japanese Unexamined Patent Application Publication H4-34316 (“the JP '316”). Moreover, while not illustrated in the details in the JP '316, typically, in the flow meter, no sensor for measuring the temperature and pressure within the main unit is provided within the main unit, so a sensor is screwed into a boss, which is provided on the main unit, so as to be installed separately, outside of the main unit. Moreover, copper wires (communicating wires) for connecting between the sensor and a counter portion are exposed on the outside.
However, in the conventional technology it is necessary to install a separate sensor, through screwing in, or the like, on the outside of the main unit, and thus the structure is one wherein the communication lines of the sensor for measuring the temperature and pressure are exposed on the outside of the main unit, not only having a deleterious impact on the appearance of the flow meter, but also having a problem in that there is a strong possibility that the wires could get pulled out or have conductivity faults.
The present invention was created in order to solve issues such as the above, and an aspect thereof is to provide a flow meter wherein the sensor for measuring the temperature and the pressure, and the communication lines, are installed within a case, thereby maintaining the actual appearance of the flow meter and preventing the sensor and wires from being pulled off.